palacios/src/devices/lnx_virtio_blk.c

   1 /*
   2  * This file is part of the Palacios Virtual Machine Monitor developed
   3  * by the V3VEE Project with funding from the United States National
   4  * Science Foundation and the Department of Energy.
   5  *
   6  * The V3VEE Project is a joint project between Northwestern University
   7  * and the University of New Mexico.  You can find out more at
   8  * http://www.v3vee.org
   9  *
  10  * Copyright (c) 2008, Jack Lange <jarusl@cs.northwestern.edu>
  11  * Copyright (c) 2008, The V3VEE Project <http://www.v3vee.org>
  12  * All rights reserved.
  13  *
  14  * Author: Jack Lange <jarusl@cs.northwestern.edu>
  15  *
  16  * This is free software.  You are permitted to use,
  17  * redistribute, and modify it as specified in the file "V3VEE_LICENSE".
  18  */
  19
  20 #include <palacios/vmm.h>
  21 #include <palacios/vmm_dev_mgr.h>
  22 #include <devices/lnx_virtio_pci.h>
  23 #include <palacios/vm_guest_mem.h>
  24
  25 #include <devices/pci.h>
  26
  27
  28
  29 #ifndef CONFIG_DEBUG_VIRTIO_BLK
  30 #undef PrintDebug
  31 #define PrintDebug(fmt, args...)
  32 #endif
  33
  34
  35 #define SECTOR_SIZE 512
  36
  37 #define BLK_CAPACITY_PORT     20
  38 #define BLK_MAX_SIZE_PORT     28
  39 #define BLK_MAX_SEG_PORT      32
  40 #define BLK_CYLINDERS_PORT    36
  41 #define BLK_HEADS_PORT        38
  42 #define BLK_SECTS_PORT        39
  43
  44 #define BLK_IN_REQ            0
  45 #define BLK_OUT_REQ           1
  46 #define BLK_SCSI_CMD          2
  47
  48 #define BLK_BARRIER_FLAG     0x80000000
  49
  50 #define BLK_STATUS_OK             0
  51 #define BLK_STATUS_ERR            1
  52 #define BLK_STATUS_NOT_SUPPORTED  2
  53
  54
  55 struct blk_config {
  56     uint64_t capacity;
  57     uint32_t max_size;
  58     uint32_t max_seg;
  59     uint16_t cylinders;
  60     uint8_t heads;
  61     uint8_t sectors;
  62 } __attribute__((packed));
  63
  64
  65
  66 struct blk_op_hdr {
  67     uint32_t type;
  68     uint32_t prior;
  69     uint64_t sector;
  70 } __attribute__((packed));
  71
  72 #define QUEUE_SIZE 128
  73
  74 /* Host Feature flags */
  75 #define VIRTIO_BARRIER       0x01       /* Does host support barriers? */
  76 #define VIRTIO_SIZE_MAX      0x02       /* Indicates maximum segment size */
  77 #define VIRTIO_SEG_MAX       0x04       /* Indicates maximum # of segments */
  78 #define VIRTIO_LEGACY_GEOM   0x10       /* Indicates support of legacy geometry */
  79
  80
  81 struct virtio_dev_state {
  82     struct vm_device * pci_bus;
  83     struct list_head dev_list;
  84     struct guest_info * vm;
  85 };
  86
  87 struct virtio_blk_state {
  88
  89     struct pci_device * pci_dev;
  90     struct blk_config block_cfg;
  91     struct virtio_config virtio_cfg;
  92
  93
  94     struct virtio_queue queue;
  95
  96     struct v3_dev_blk_ops * ops;
  97
  98     void * backend_data;
  99
 100     int io_range_size;
 101
 102     struct virtio_dev_state * virtio_dev;
 103
 104     struct list_head dev_link;
 105 };
 106
 107
 108 static int virtio_free(struct vm_device * dev) {
 109     return -1;
 110 }
 111
 112 static int blk_reset(struct virtio_blk_state * virtio) {
 113
 114     virtio->queue.ring_desc_addr = 0;
 115     virtio->queue.ring_avail_addr = 0;
 116     virtio->queue.ring_used_addr = 0;
 117     virtio->queue.pfn = 0;
 118     virtio->queue.cur_avail_idx = 0;
 119
 120     virtio->virtio_cfg.status = 0;
 121     virtio->virtio_cfg.pci_isr = 0;
 122     return 0;
 123 }
 124
 125
 126 static int virtio_reset(struct vm_device * dev) {
 127     struct virtio_dev_state * dev_state = (struct virtio_dev_state *)(dev->private_data);
 128     struct virtio_blk_state * blk_state = NULL;
 129
 130     list_for_each_entry(blk_state, &(dev_state->dev_list), dev_link) {
 131         blk_reset(blk_state);
 132     }
 133
 134     return 0;
 135 }
 136
 137 static int handle_read_op(struct virtio_blk_state * blk_state, uint8_t * buf, uint64_t * sector, uint64_t len) {
 138     int ret = -1;
 139
 140     PrintDebug("Reading Disk\n");
 141     ret = blk_state->ops->read(buf, (*sector) * SECTOR_SIZE, len, (void *)(blk_state->backend_data));
 142     *sector += (len / SECTOR_SIZE);
 143
 144     return ret;
 145 }
 146
 147
 148 static int handle_write_op(struct virtio_blk_state * blk_state, uint8_t * buf, uint64_t * sector, uint64_t len) {
 149     int ret = -1;
 150
 151     PrintDebug("Writing Disk\n");
 152     ret = blk_state->ops->write(buf, (*sector) * SECTOR_SIZE, len, (void *)(blk_state->backend_data));
 153     *sector += (len / SECTOR_SIZE);
 154
 155     return ret;
 156 }
 157
 158
 159
 160 // multiple block operations need to increment the sector
 161
 162 static int handle_block_op(struct virtio_blk_state * blk_state, struct blk_op_hdr * hdr,
 163                            struct vring_desc * buf_desc, uint8_t * status) {
 164     uint8_t * buf = NULL;
 165
 166     PrintDebug("Handling Block op\n");
 167     if (guest_pa_to_host_va(blk_state->virtio_dev->vm, buf_desc->addr_gpa, (addr_t *)&(buf)) == -1) {
 168         PrintError("Could not translate buffer address\n");
 169         return -1;
 170     }
 171
 172     PrintDebug("Sector=%p Length=%d\n", (void *)(addr_t)(hdr->sector), buf_desc->length);
 173
 174     if (hdr->type == BLK_IN_REQ) {
 175         if (handle_read_op(blk_state, buf, &(hdr->sector), buf_desc->length) == -1) {
 176             *status = BLK_STATUS_ERR;
 177             return -1;
 178         } else {
 179             *status = BLK_STATUS_OK;
 180         }
 181     } else if (hdr->type == BLK_OUT_REQ) {
 182         if (handle_write_op(blk_state, buf, &(hdr->sector), buf_desc->length) == -1) {
 183             *status = BLK_STATUS_ERR;
 184             return -1;
 185         } else {
 186             *status = BLK_STATUS_OK;
 187         }
 188     } else if (hdr->type == BLK_SCSI_CMD) {
 189         PrintError("VIRTIO: SCSI Command Not supported!!!\n");
 190         *status = BLK_STATUS_NOT_SUPPORTED;
 191         return -1;
 192     }
 193
 194     PrintDebug("Returning Status: %d\n", *status);
 195
 196     return 0;
 197 }
 198
 199 static int get_desc_count(struct virtio_queue * q, int index) {
 200     struct vring_desc * tmp_desc = &(q->desc[index]);
 201     int cnt = 1;
 202
 203     while (tmp_desc->flags & VIRTIO_NEXT_FLAG) {
 204         tmp_desc = &(q->desc[tmp_desc->next]);
 205         cnt++;
 206     }
 207
 208     return cnt;
 209 }
 210
 211
 212
 213 static int handle_kick(struct virtio_blk_state * blk_state) {
 214     struct virtio_queue * q = &(blk_state->queue);
 215
 216     PrintDebug("VIRTIO KICK: cur_index=%d (mod=%d), avail_index=%d\n",
 217                q->cur_avail_idx, q->cur_avail_idx % QUEUE_SIZE, q->avail->index);
 218
 219     while (q->cur_avail_idx < q->avail->index) {
 220         struct vring_desc * hdr_desc = NULL;
 221         struct vring_desc * buf_desc = NULL;
 222         struct vring_desc * status_desc = NULL;
 223         struct blk_op_hdr hdr;
 224         addr_t hdr_addr = 0;
 225         uint16_t desc_idx = q->avail->ring[q->cur_avail_idx % QUEUE_SIZE];
 226         int desc_cnt = get_desc_count(q, desc_idx);
 227         int i = 0;
 228         uint8_t * status_ptr = NULL;
 229         uint8_t status = BLK_STATUS_OK;
 230         uint32_t req_len = 0;
 231
 232         PrintDebug("Descriptor Count=%d, index=%d\n", desc_cnt, q->cur_avail_idx % QUEUE_SIZE);
 233
 234         if (desc_cnt < 3) {
 235             PrintError("Block operations must include at least 3 descriptors\n");
 236             return -1;
 237         }
 238
 239         hdr_desc = &(q->desc[desc_idx]);
 240
 241
 242         PrintDebug("Header Descriptor (ptr=%p) gpa=%p, len=%d, flags=%x, next=%d\n", hdr_desc,
 243                    (void *)(hdr_desc->addr_gpa), hdr_desc->length, hdr_desc->flags, hdr_desc->next);
 244
 245         if (guest_pa_to_host_va(blk_state->virtio_dev->vm, hdr_desc->addr_gpa, &(hdr_addr)) == -1) {
 246             PrintError("Could not translate block header address\n");
 247             return -1;
 248         }
 249
 250         // We copy the block op header out because we are going to modify its contents
 251         memcpy(&hdr, (void *)hdr_addr, sizeof(struct blk_op_hdr));
 252
 253         PrintDebug("Blk Op Hdr (ptr=%p) type=%d, sector=%p\n", (void *)hdr_addr, hdr.type, (void *)hdr.sector);
 254
 255         desc_idx = hdr_desc->next;
 256
 257         for (i = 0; i < desc_cnt - 2; i++) {
 258             uint8_t tmp_status = BLK_STATUS_OK;
 259
 260             buf_desc = &(q->desc[desc_idx]);
 261
 262             PrintDebug("Buffer Descriptor (ptr=%p) gpa=%p, len=%d, flags=%x, next=%d\n", buf_desc,
 263                        (void *)(buf_desc->addr_gpa), buf_desc->length, buf_desc->flags, buf_desc->next);
 264
 265             if (handle_block_op(blk_state, &hdr, buf_desc, &tmp_status) == -1) {
 266                 PrintError("Error handling block operation\n");
 267                 return -1;
 268             }
 269
 270             if (tmp_status != BLK_STATUS_OK) {
 271                 status = tmp_status;
 272             }
 273
 274             req_len += buf_desc->length;
 275             desc_idx = buf_desc->next;
 276         }
 277
 278         status_desc = &(q->desc[desc_idx]);
 279
 280         PrintDebug("Status Descriptor (ptr=%p) gpa=%p, len=%d, flags=%x, next=%d\n", status_desc,
 281                    (void *)(status_desc->addr_gpa), status_desc->length, status_desc->flags, status_desc->next);
 282
 283         if (guest_pa_to_host_va(blk_state->virtio_dev->vm, status_desc->addr_gpa, (addr_t *)&(status_ptr)) == -1) {
 284             PrintError("Could not translate status address\n");
 285             return -1;
 286         }
 287
 288         req_len += status_desc->length;
 289         *status_ptr = status;
 290
 291         q->used->ring[q->used->index % QUEUE_SIZE].id = q->avail->ring[q->cur_avail_idx % QUEUE_SIZE];
 292         q->used->ring[q->used->index % QUEUE_SIZE].length = req_len; // What do we set this to????
 293
 294         q->used->index++;
 295         q->cur_avail_idx++;
 296     }
 297
 298     if (!(q->avail->flags & VIRTIO_NO_IRQ_FLAG)) {
 299         PrintDebug("Raising IRQ %d\n",  blk_state->pci_dev->config_header.intr_line);
 300         v3_pci_raise_irq(blk_state->virtio_dev->pci_bus, 0, blk_state->pci_dev);
 301         blk_state->virtio_cfg.pci_isr = 1;
 302     }
 303
 304     return 0;
 305 }
 306
 307 static int virtio_io_write(uint16_t port, void * src, uint_t length, void * private_data) {
 308     struct virtio_blk_state * blk_state = (struct virtio_blk_state *)private_data;
 309     int port_idx = port % blk_state->io_range_size;
 310
 311
 312     PrintDebug("VIRTIO BLOCK Write for port %d (index=%d) len=%d, value=%x\n",
 313                port, port_idx,  length, *(uint32_t *)src);
 314
 315
 316
 317     switch (port_idx) {
 318         case GUEST_FEATURES_PORT:
 319             if (length != 4) {
 320                 PrintError("Illegal write length for guest features\n");
 321                 return -1;
 322             }
 323
 324             blk_state->virtio_cfg.guest_features = *(uint32_t *)src;
 325             PrintDebug("Setting Guest Features to %x\n", blk_state->virtio_cfg.guest_features);
 326
 327             break;
 328         case VRING_PG_NUM_PORT:
 329             if (length == 4) {
 330                 addr_t pfn = *(uint32_t *)src;
 331                 addr_t page_addr = (pfn << VIRTIO_PAGE_SHIFT);
 332
 333
 334                 blk_state->queue.pfn = pfn;
 335
 336                 blk_state->queue.ring_desc_addr = page_addr ;
 337                 blk_state->queue.ring_avail_addr = page_addr + (QUEUE_SIZE * sizeof(struct vring_desc));
 338                 blk_state->queue.ring_used_addr = ( blk_state->queue.ring_avail_addr + \
 339                                                  sizeof(struct vring_avail)    + \
 340                                                  (QUEUE_SIZE * sizeof(uint16_t)));
 341
 342                 // round up to next page boundary.
 343                 blk_state->queue.ring_used_addr = (blk_state->queue.ring_used_addr + 0xfff) & ~0xfff;
 344
 345                 if (guest_pa_to_host_va(blk_state->virtio_dev->vm, blk_state->queue.ring_desc_addr, (addr_t *)&(blk_state->queue.desc)) == -1) {
 346                     PrintError("Could not translate ring descriptor address\n");
 347                     return -1;
 348                 }
 349
 350
 351                 if (guest_pa_to_host_va(blk_state->virtio_dev->vm, blk_state->queue.ring_avail_addr, (addr_t *)&(blk_state->queue.avail)) == -1) {
 352                     PrintError("Could not translate ring available address\n");
 353                     return -1;
 354                 }
 355
 356
 357                 if (guest_pa_to_host_va(blk_state->virtio_dev->vm, blk_state->queue.ring_used_addr, (addr_t *)&(blk_state->queue.used)) == -1) {
 358                     PrintError("Could not translate ring used address\n");
 359                     return -1;
 360                 }
 361
 362                 PrintDebug("RingDesc_addr=%p, Avail_addr=%p, Used_addr=%p\n",
 363                            (void *)(blk_state->queue.ring_desc_addr),
 364                            (void *)(blk_state->queue.ring_avail_addr),
 365                            (void *)(blk_state->queue.ring_used_addr));
 366
 367                 PrintDebug("RingDesc=%p, Avail=%p, Used=%p\n",
 368                            blk_state->queue.desc, blk_state->queue.avail, blk_state->queue.used);
 369
 370             } else {
 371                 PrintError("Illegal write length for page frame number\n");
 372                 return -1;
 373             }
 374             break;
 375         case VRING_Q_SEL_PORT:
 376             blk_state->virtio_cfg.vring_queue_selector = *(uint16_t *)src;
 377
 378             if (blk_state->virtio_cfg.vring_queue_selector != 0) {
 379                 PrintError("Virtio Block device only uses 1 queue, selected %d\n",
 380                            blk_state->virtio_cfg.vring_queue_selector);
 381                 return -1;
 382             }
 383
 384             break;
 385         case VRING_Q_NOTIFY_PORT:
 386             PrintDebug("Handling Kick\n");
 387             if (handle_kick(blk_state) == -1) {
 388                 PrintError("Could not handle Block Notification\n");
 389                 return -1;
 390             }
 391             break;
 392         case VIRTIO_STATUS_PORT:
 393             blk_state->virtio_cfg.status = *(uint8_t *)src;
 394
 395             if (blk_state->virtio_cfg.status == 0) {
 396                 PrintDebug("Resetting device\n");
 397                 blk_reset(blk_state);
 398             }
 399
 400             break;
 401
 402         case VIRTIO_ISR_PORT:
 403             blk_state->virtio_cfg.pci_isr = *(uint8_t *)src;
 404             break;
 405         default:
 406             return -1;
 407             break;
 408     }
 409
 410     return length;
 411 }
 412
 413
 414 static int virtio_io_read(uint16_t port, void * dst, uint_t length, void * private_data) {
 415     struct virtio_blk_state * blk_state = (struct virtio_blk_state *)private_data;
 416     int port_idx = port % blk_state->io_range_size;
 417
 418
 419     PrintDebug("VIRTIO BLOCK Read  for port %d (index =%d), length=%d\n",
 420                port, port_idx, length);
 421
 422     switch (port_idx) {
 423         case HOST_FEATURES_PORT:
 424             if (length != 4) {
 425                 PrintError("Illegal read length for host features\n");
 426                 return -1;
 427             }
 428
 429             *(uint32_t *)dst = blk_state->virtio_cfg.host_features;
 430
 431             break;
 432         case VRING_PG_NUM_PORT:
 433             if (length != 4) {
 434                 PrintError("Illegal read length for page frame number\n");
 435                 return -1;
 436             }
 437
 438             *(uint32_t *)dst = blk_state->queue.pfn;
 439
 440             break;
 441         case VRING_SIZE_PORT:
 442             if (length != 2) {
 443                 PrintError("Illegal read length for vring size\n");
 444                 return -1;
 445             }
 446
 447             *(uint16_t *)dst = blk_state->queue.queue_size;
 448
 449             break;
 450
 451         case VIRTIO_STATUS_PORT:
 452             if (length != 1) {
 453                 PrintError("Illegal read length for status\n");
 454                 return -1;
 455             }
 456
 457             *(uint8_t *)dst = blk_state->virtio_cfg.status;
 458             break;
 459
 460         case VIRTIO_ISR_PORT:
 461             *(uint8_t *)dst = blk_state->virtio_cfg.pci_isr;
 462             blk_state->virtio_cfg.pci_isr = 0;
 463             v3_pci_lower_irq(blk_state->virtio_dev->pci_bus, 0, blk_state->pci_dev);
 464             break;
 465
 466         default:
 467             if ( (port_idx >= sizeof(struct virtio_config)) &&
 468                  (port_idx < (sizeof(struct virtio_config) + sizeof(struct blk_config))) ) {
 469                 int cfg_offset = port_idx - sizeof(struct virtio_config);
 470                 uint8_t * cfg_ptr = (uint8_t *)&(blk_state->block_cfg);
 471
 472                 memcpy(dst, cfg_ptr + cfg_offset, length);
 473
 474             } else {
 475                 PrintError("Read of Unhandled Virtio Read\n");
 476                 return -1;
 477             }
 478
 479             break;
 480     }
 481
 482     return length;
 483 }
 484
 485
 486
 487
 488 static struct v3_device_ops dev_ops = {
 489     .free = virtio_free,
 490     .reset = virtio_reset,
 491     .start = NULL,
 492     .stop = NULL,
 493 };
 494
 495
 496
 497
 498
 499 static int register_dev(struct virtio_dev_state * virtio, struct virtio_blk_state * blk_state) {
 500     // initialize PCI
 501     struct pci_device * pci_dev = NULL;
 502     struct v3_pci_bar bars[6];
 503     int num_ports = sizeof(struct virtio_config) + sizeof(struct blk_config);
 504     int tmp_ports = num_ports;
 505     int i;
 506
 507
 508
 509     // This gets the number of ports, rounded up to a power of 2
 510     blk_state->io_range_size = 1; // must be a power of 2
 511
 512     while (tmp_ports > 0) {
 513         tmp_ports >>= 1;
 514         blk_state->io_range_size <<= 1;
 515     }
 516
 517     // this is to account for any low order bits being set in num_ports
 518     // if there are none, then num_ports was already a power of 2 so we shift right to reset it
 519     if ((num_ports & ((blk_state->io_range_size >> 1) - 1)) == 0) {
 520         blk_state->io_range_size >>= 1;
 521     }
 522
 523
 524     for (i = 0; i < 6; i++) {
 525         bars[i].type = PCI_BAR_NONE;
 526     }
 527
 528     PrintDebug("Virtio-BLK io_range_size = %d\n", blk_state->io_range_size);
 529
 530     bars[0].type = PCI_BAR_IO;
 531     bars[0].default_base_port = -1;
 532     bars[0].num_ports = blk_state->io_range_size;
 533
 534     bars[0].io_read = virtio_io_read;
 535     bars[0].io_write = virtio_io_write;
 536     bars[0].private_data = blk_state;
 537
 538     pci_dev = v3_pci_register_device(virtio->pci_bus, PCI_STD_DEVICE,
 539                                      0, PCI_AUTO_DEV_NUM, 0,
 540                                      "LNX_VIRTIO_BLK", bars,
 541                                      NULL, NULL, NULL, blk_state);
 542
 543     if (!pci_dev) {
 544         PrintError("Could not register PCI Device\n");
 545         return -1;
 546     }
 547
 548     pci_dev->config_header.vendor_id = VIRTIO_VENDOR_ID;
 549     pci_dev->config_header.subsystem_vendor_id = VIRTIO_SUBVENDOR_ID;
 550
 551
 552     pci_dev->config_header.device_id = VIRTIO_BLOCK_DEV_ID;
 553     pci_dev->config_header.class = PCI_CLASS_STORAGE;
 554     pci_dev->config_header.subclass = PCI_STORAGE_SUBCLASS_OTHER;
 555
 556     pci_dev->config_header.subsystem_id = VIRTIO_BLOCK_SUBDEVICE_ID;
 557
 558
 559     pci_dev->config_header.intr_pin = 1;
 560
 561     pci_dev->config_header.max_latency = 1; // ?? (qemu does it...)
 562
 563
 564     blk_state->pci_dev = pci_dev;
 565
 566     /* Block configuration */
 567     blk_state->virtio_cfg.host_features = VIRTIO_SEG_MAX;
 568     blk_state->block_cfg.max_seg = QUEUE_SIZE - 2;
 569
 570     // Virtio Block only uses one queue
 571     blk_state->queue.queue_size = QUEUE_SIZE;
 572
 573     blk_state->virtio_dev = virtio;
 574
 575     blk_reset(blk_state);
 576
 577
 578     return 0;
 579 }
 580
 581
 582 static int connect_fn(struct guest_info * info,
 583                       void * frontend_data,
 584                       struct v3_dev_blk_ops * ops,
 585                       v3_cfg_tree_t * cfg,
 586                       void * private_data) {
 587
 588     struct virtio_dev_state * virtio = (struct virtio_dev_state *)frontend_data;
 589
 590     struct virtio_blk_state * blk_state  = (struct virtio_blk_state *)V3_Malloc(sizeof(struct virtio_blk_state));
 591     memset(blk_state, 0, sizeof(struct virtio_blk_state));
 592
 593     register_dev(virtio, blk_state);
 594
 595     blk_state->ops = ops;
 596     blk_state->backend_data = private_data;
 597
 598     blk_state->block_cfg.capacity = ops->get_capacity(private_data) / SECTOR_SIZE;
 599
 600     PrintDebug("Virtio Capacity = %d -- 0x%p\n", (int)(blk_state->block_cfg.capacity),
 601                (void *)(addr_t)(blk_state->block_cfg.capacity));
 602
 603     return 0;
 604 }
 605
 606
 607 static int virtio_init(struct guest_info * vm, v3_cfg_tree_t * cfg) {
 608     struct vm_device * pci_bus = v3_find_dev(vm, v3_cfg_val(cfg, "bus"));
 609     struct virtio_dev_state * virtio_state = NULL;
 610     char * name = v3_cfg_val(cfg, "name");
 611
 612     PrintDebug("Initializing VIRTIO Block device\n");
 613
 614     if (pci_bus == NULL) {
 615         PrintError("VirtIO devices require a PCI Bus");
 616         return -1;
 617     }
 618
 619
 620     virtio_state  = (struct virtio_dev_state *)V3_Malloc(sizeof(struct virtio_dev_state));
 621     memset(virtio_state, 0, sizeof(struct virtio_dev_state));
 622
 623     INIT_LIST_HEAD(&(virtio_state->dev_list));
 624     virtio_state->pci_bus = pci_bus;
 625     virtio_state->vm = vm;
 626
 627     struct vm_device * dev = v3_allocate_device(name, &dev_ops, virtio_state);
 628     if (v3_attach_device(vm, dev) == -1) {
 629         PrintError("Could not attach device %s\n", name);
 630         return -1;
 631     }
 632
 633     if (v3_dev_add_blk_frontend(vm, name, connect_fn, (void *)virtio_state) == -1) {
 634         PrintError("Could not register %s as block frontend\n", name);
 635         return -1;
 636     }
 637
 638     return 0;
 639 }
 640
 641
 642 device_register("LNX_VIRTIO_BLK", virtio_init)